Police were called to a Concord property following reports of a domestic dispute.
The AOS was called as a precaution as the man had access to a firearm, Senior Sergeant Brian Benn, of Dunedin, said.
A cordon was put in place around the Stevenson Rd property and nearby Concord School was placed in lockdown.
Principal Steve Turnbull said the pupils were locked inside the school hall, where they had their lunch.
Snr Sgt Benn said no threats were made and the man was taken into custody ''without incident''.
The man was charged with a firearm offence and threatening behaviour.